Liquid supply means with mixing device



Oct. 22, 1963 J. ISREELI 'ETAL 3,107,537

LIQUID SUPPLY MEANS WITH MIXING DEVICE Filed NOV. 2, 1961 2 Sheets-She et l INVENTORS Jaw /SI?EEL/ I BY 7I IEODOQE BlL/cmv/alvskr ATTcw vev United States Patent LIQUID SUPPLY MEANS WITH MIXING DEVICE Jack Isreeli, Tuckahoe, and Theodore Bilichniansky,

Pleasant Valley, N.Y., assignors to Technicon Insh'uments Corporation, Chauncey, N.Y., a corporation of New York Filed Nov. 2, 1961, Ser. No. 149,673 9 Claims. (Cl. 73-423) This invention relates to liquid supply means, especially sample-supply means for automaticv liquid-analysis apparatus and, more particularly, to the provision of improved means for mixing or stirring the liquid in at least certain of the sample-supply cups or receptacles.

In the case of'certain liquids which may contain matter which tends to settle out, it is necessary or desirable to stir the liquid before or even while the liquid sample is being removed from the cups by the liquid take-off device of the sample-supply means. For example, but without limitation, in the clinical analysis of blood hemoglobin, determinations are made on whole blood specimens which must be well mixed and in homgeneous condition when aspirated or otherwise withdrawn from the sample cups for transmission to the automatic analysis apparatus.

One of the objects of the present invention is to provide improved means for thoroughly mixing the liquid samples so that they are in homogeneous condition at the time of their removal from the cups by the take-on device of the sample-supply apparatus. More specifically, in accordance with this object of the invention, the mixing device comprises vibratory stirring means actuated by an electric solenoid and movable as a unit with the liquid withdrawing device into and out of the receptacles at the liquid take-off position.

The above and other objects, features and advantages of the invention will be apparent from the following description of the presently preferred embodiment of the invention, considered in connection with the accompanying illustrated drawings.

In the drawings:

FIG. 1 is a top plan view of sample-supply means embodying the invention;

FIG. 2 is a side view, partly in section on the line 2-2 of FIG. 1, showing the take-ofi means and the stirring means in operative positions;

FIG. 3 is a view on a large scale partly in elevation and partly in section on the line 33 of FIG. 2;

FIG. 4 is a top plan view of part of the sample-supply means, with parts broken away or omitted for clarification of the illustration;

FIG. 5 is a sectional view on the line 5-5 of FIG. 4; and

FIG. 6 is a sectional view on the line 6-6 of FIG. 2.

Referring now to the drawings in detail, the samplesupply means, briefly described, comprises a carrier, here shown as a turn-table 10 which is intermittently turned by suitable mechanism disposed within a housing 12, said mechanism being illustrated by FIGS. 4 and 5 and hereinafter more particularly described. The turn-table comprises a plate '16 which carries a series of removable cups 18 for the liquid samples, said cups being disposed laterally of each other in a circular row. For this purpose plate 16 is provided with a series of holes 20 and the cups have a peripheral shoulder 22 which rests on the marginal edge of the plate around the opening through which the cup projects as shown by FIGS. 2. and 3.

The take-off device 24 and the mixer 26 are mounted on the housing or base 12 in the position shown by FIG. 1 and comprise parts which are movable to and from the position illustrated by FIG. 2 in timed relation to the step movement of the turn-table so that during each rest period of the latter the take-off tube 28 of the take-off device and one or more stirrer members 30 are moved into and out of the cups when the latter are positioned at the station of said take-off device and at the station or stations of the mixer 26. As here shown (FIGS. 2 and 3), the mixer 26 comprises two vibratory stirrers 30,

1 one for the cup which is positioned immediately before bar 451 which has slotted end portions 63, as shown more the take-off position; one for the cup which is positioned at the take-off position, as illustrated by FIG. 3, it being noted that the turn-table It} is movable clockwise, viewing FIG. 1. The stirrer provided for the cup at the takeoff position is operable to stir the liquid while it is being withdrawn from the cup and thus maintain the liquid previously stirred by the other stirrer in well mixed condition and prevents settling of matter from the liquid at the take-off position. This is desirable and sometimes necessary in the case of liquids which contain matter which would otherwise settle out rapidly, but ordinarily the mixer need have only the stirrer for the cup next to the take-01f position.

The stirrer comprises a metal spindle or prong 32 which fits within and is enclosed by a polyethylene tube 34 which is inert to the sample liquid. The lower end 36 of said tube. extends a short distance below the lower end of the companion spindle and is flattened to provide a paddle-like element to improve the stirring action. The opposite side walls of the tube at the flattened portion may be held together in flat condition by heat fusing them or in any other suitable way. The polyethylene tubes 34 are substantially non-wettable and hence do not carry sample liquid from one cup to another. The non-wettable property of polyethylene is thus valuable to the present invention.

Stirrers 30* are in unitary integral relation with an inverted U-shaped member 38 which is vibrated rapidly by electromagnetic means, preferably solenoid 40 operable with alternating current, say the usual 60 cycle alternating current at about 110 volts. Solenoid 40* is mounted in an aluminum housing 42, being disposed within the soft iron member 44- which provides a good path for the magnetic flux generated by the solenoid coil. Said member 44 has an upper part 45 secured in the housing by screws 46, a side part 47 spaced from the adjacent side wall 48 of the housing, and a bottom part 49 which underlies the solenoid 4t} and also closes the bottom of that part of the housing in which the solenoid is positioned. Soft iron members 49' and 50 are carried by the nonmetallic spool 51 of the solenoid coil 52 and are secured in position at the top of housing 42 by the previously mentioned screws 46'.

Members 53 and 54 formed of fiat spring steel are secured in the housing between part 45 and the underlying part of member 49 by screw '46. Member 5-3 extends outwardly of the housing 42 and terminates in a U-shaped part '55 in which the upper end 56 of member 38 is supported and from which member 33 depends in v the operative position thereof. Part also provides a pivotal support for member 38 to enable said member to be turned in an upward direction clear of the cups on plate 16 of the turn-table when the take-off device is in a retracted position, so as to-permit samplecups or receptacles to be removed and replaced when desired at the take-off position. Spring member 54 also extends outwardly of the housing 42 and terminates in a downwardly extending part 57 which has a concave lower portion 58 which abuts the adjacent end face of the solenoid plunger 60 and which is in contact with the soft iron clearly in FIG. 6, which are clamped to the laterally spaced arms 64 and vibratory member 38 for securement thereto.

As is clearly shown by FIG. 6, a metal core piece 65 is secured in fixed position in the solenoid member 51 in which the solenoid plunger 60 has a sliding fit, and a compression spring 66 is interposed between the confronting ends of the plunger 60 and said core piece 65. Said spring 66 biases the plunger 60 for movement toward member 38 and moves said plunger a short distance against the counteracting force of spring member 57 when the solenoid coil is energized by the alternating current during that half of its cycle which is in magnetic repelling relation to the solenoid plunger when the latter is a permanent magnet pursuant to the preferred embodiment of the invention. On the other hand, when the energizing current is in the reverse half of its cycle so that it is in magnetically attracting relation to plunger 6%) for drawing the plunger into the solenoid coil, spring 60 is compressed and acts as a resilient stop in the inward movement of the solenoid plunger besides acting to move the solenoid plunger in the opposite direction at the zero point of the alternating current cycle. It will be under stood that member 61 being made of soft iron acts as an armature and is electro-magnetically coupled to the plunger 60, so that it follows the rapid motion of plunger 60 in opposite direction and is moved rapidly in opposite directions longitudinally of the path of the solenoid plunger. It will be noted that the amplitude of movement of the solenoid plunger is small with a concomitant small amplitude of vibration of member 38 and the stirrers 30 carried thereby. As will be readily understood, the ampere-turns of solenoid coil 40 should be low enough so that the permanent magnetic plunger 60 is not demagnetized by the alternating current flowing through said coil. It will be understood that while the solenoid plunger 60 is preferably a permanent magnet, it is Within the scope of the invention to utilize a solenoid plunger of soft iron in which case the speed of vibration of the plunger and the corresponding speed of vibration of the member 38 is higher than that which obtains when the solenoid plunger is a permanent magnet, but in the case of a soft iron plunger, the amplitude is smaller than when the plunger is a permanent magnet because in the latter case the field of the solenoid coil and the spring 66 are in additive relation when thefield of the solenoid is of the same polarity as the inner end part of the solenoid.

As here shown, the mixer 26 is mounted for movement to and from operative and retracted positions as a unit with the movable part 67 of the take-off device 24. Said part 67 is a tubular metal crook through which the take-off tube 28 formed of polyethylene tubing extends for connection to the pump (not shown) of the analysis apparatus whereby the sample liquid is aspirated from the cup at the take-off position. Said crook 67 is pivotally movable and is mounted for pivotal movement to and from said operative and retracted positions as described in the U5. Patent No. 3,038,340, issued June 12, 1962, and assigned to the assignee of the present application. As here shown, a spindle 68 is mounted for pivotal movement in bracket 69 secured to the top of housing 12. Said crook 67 is mounted on a movable support 70 by the member 71 which is secured to the crook and is secured to support 70 by a set screw 72. Movable support 70 is a rod which is fixed to and held by the part 68a of spindle 68 so as to move in an arcuate path in the slot 70a in the top of housing 12. A normally open switch 70b is supported in housing 12 (FIG. 2) in position to be closed by rod when the stirrers are in the liquid-holding means so that the solenoid coil is energized only when the stirrers are in the liquid. Mixer 26 is secured to the arcuate part 67a of the crook by clamping said arcuate part between the parts 47 and 48 of the field member 44 and housing 42, respectively, by means of the clamping screws 73, the heads of which engage the outer surface of part 48 and shanks of which are threaded into tapped holes into part 47. A screw 74 is secured to said part 47 above screws 73 to act as a positioning abutment for the upper end of crook 67 within the housing 42. The crook terminates in the end 75 a short distance below the lower end of housing 42 and the intake end portion of tube 28 projects downwardly beyond said end 75 of the crook into the cup 18 at the take-off position.

The mechanism for turning the turn-table 10 and for effecting the pivotal movements of rock shaft 68 is described in detail in the above mentioned Isreeli patent application. As more fully described in said Isreeli application, a Geneva gear 76 is mounted on a shaft 77 which is secured to a plate 78 of housing 12. A pinion gear 79 is mounted for rotation on a shaft 77 and Geneva gear 76 is secured to said pinion gear. Gear 7 9 is in mesh with an intermediate gear 80 which is in mesh with a driven gear 31 and said gear 80 is secured to a drive shaft 82 to which the turn-table 10 is secured for intermittent rotation.

The driver for Geneva gear 76 is constituted by a pin 81 which projects upwardly from a set of stacked gears 82 which is part of a speed change mechanism operated by the lever 84 shown in FIG. 4. An electric motor, not shown, turns a gear 86 which meshes with one of the stacked gears 82, depending upon the vertical position of gear 86, as set by the operation of lever 84, to drive pin 80 which drives the Geneva gear 76 for intermittently rotating the turn-table.

The pivotal movements of the take-off tube are also effected by the operation of pin 31. More specifically, a cam member 88 is pivotally mounted at 90, at one end thereof, and the free end of the cam member is interconnected by the tension spring 92 with the lower end of a pin 94 which is secured to plate 78. A wire link 96 interconnects the free end of cam member 88 and the lower end of rod 70. When cam member 88 is in the retracted (broken line) position illustrated in FIG. 4, the takeoff tube 28 and the stirrer 32 are withdrawn from the cups. Cam member 88 has an arcuate part 98, and when the stacked gears rotate counterclockwise, as viewed in FIG. 4, before pin 80 engages a slot in the Geneva gear 76 to rotate table 10, the pin will first strike the cam member, which is in the path of movement thereof, and pivot said cam member from the full to the broken line position thereof, with the pin riding along the arcuate portion 98 during the period that it remains engaged in a slot in said Geneva gear 76. When pin 81 disengages the slot of the Geneva gear, said pin also disengages cam member 88 and the latter is thereupon moved to its fullline position by spring 92 and the take-off tube and stirrer are inserted into the sample cups. These movements of eam member 88 result in moving the take-off tube and the stirrer into and out of the cups while the turn-table is stationary.

Thus it is seen that the liquid-holder means and the liquid take-off means are relatively movable to and from operative positions for the flow of liquid from the receptacles through said take-ofi means, and that the vibratory stirring means is effective by its rapid vibrations in the liquid to agitate the liquid and thereby stir it and keep it in homogeneous condition. We have found that an amplitude of vibration of ,5 inch of the lower end of spindle 32 at the speed of sixty vibrations per second gives excellent results, but it will be understood that these are non-limitative.

While we have shown and described the preferred embodiment of our invention, it will be understood that the invention may be embodied otherwise than as herein specifically illustrated or described, and that certain changes in the form and arrangement of parts and in the specific manner of practicing the invention may be made without departing from the underlying idea or principles of this invention within the scope of the appended claims.

What is claimed is:

1. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-oil means for the flow of predetermined portions of liquid from the liquid-holding means through said take-01f means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

(b) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magneticallyresponsive carrier and a stirrer member fixed to said carrier for vibration therewith;

(d) electro-magnetic means for actuating said magnetically-responsive carrier, and means for electro-magnetically coupling said electro-magnetic means to said carrier.

2. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-off means for the flow of predetermined portions of liquid from the liquid-holding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-01f means;

(b) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magneticallyresponsive carrier and a stirrer member fixed to said carrier for vibration therewith; and

(d) solenoid means having a permanently magnetized plunger electro-magnetically coupled to said carrier for vibrating said carrier and thereby vibrating said stirrer member.

3. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-off means for the flow of predetermined portions of liquid from the liquidholding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

(b) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magneticallyresponsive slotted carrier and a stirrer member fixed to said carrier in the slots thereof for vibration therewith;

(d) solenoid means having a plunger of soft iron electro-magnetically coupled to said carrier for vibrating said carrier and thereby vibrating said stirrer member; and

(e) spring means acting on said plunger to resiliently oppose the movement of said plunger into the coil of the solenoid and for biasing the plunger for movement in the opposite direction for corresponding movement of said carrier thereby.

4. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-off means for the flow of predetermined portions of liquid from the liquid-holding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

(b) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magneticallyresponsive slotted carrier and a stirrer member fixed to said carrier via slots in said carrier for vibration therewith;

(d) solenoid means having a plunger electro-magnetically coupled to said carrier for vibrating said carrier and thereby vibrating said stirrer member;

(e) spring means acting on said plunger to resiliently oppose the movement of said plunger into the coil of the solenoid and for biasing the plunger for movement in the opposite direction for corresponding movement of said carrier thereby; and

(1) spring means acting on said carrier for opposing said bias when the solenoid coil is deenergized.

5. In liquid supply apparatus:

, (a) relatively movable liquid-holding means and liquid take-off means for the flow of predetermined portions of liquid from the liquid-holding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

([2) electro-rnagnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means; t

(c) said vibratory means comprising a magneticallyresponsive carrier and a stirrer member fixed to said carrier for vibration therewith;

(a') solenoid means having a permanently magnetized plunger electro-magnetically coupled to said carrier for vibrating said carrier and thereby vibrating said stirrer member;

(a) spring means acting on said plunger to resiliently oppose the movement of said plunger into the coil of the solenoid and for biasing the plunger for movement in the opposite direction for corresponding movement of said carrier thereby; and

(f) spring means acting on said carrier for opposing said bias when the solenoid coil is deenergized.

6. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-oft means for the flow of predetermined portions of liquid from the liquid-holding means through said take-0d means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

(12) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magneticallyresponsive carrier and a stirrer member fixed to said carrier for vibration therewith;

(d) electro-magnetic means for actuating said magnetically-responsive carrier and being only electro-magnetically coupled thereto; and

(e) means mounting said carrier for movement to and from a position in operative relation to said electromagnetic means and to and from a position in which said vibratory means is retracted from said operative relation to said electro-magnetic means when said vibratory means is also retracted from liquid stirring position to a position in which it is inoperative to stir the liquid.

7. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-oil means for the flow of predetermined portions of liquid from the liquid-holding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

(b) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magnetically-- responsive carrier and a stirrer member fixed to said carrier for vibration therewith; V a l (d) electro-magnetic means for actuating said magneti- (1) means for moving said liquid take-ofi means in succession into different liquid portions in the liquidholding means and concomitantly stirring predetermined liquid portions in said liquid-holding means means by operation of said vibratory means.

8. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-off means for the flow of predetermined portions of liquid from the liquid-holding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

([2) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

() said vibratory means comprising a magneticallyresponsive carrier and a stirrer member fixed to said carried for vibration therewith;

(d) electro-magnet'ic means for actuating said magnetically-responsive carrier and being only electro-magnetically coupled thereto;

(2) a housing for said electro-magnetic means mounted on said take-oil means;

(f) said housing having a part connected thereto for pivotally supporting the stirrer carrier; and

g) means for sequentially pivoting said housing for moving said liquid take-off means in succession into difierent liquid portions in the liquid-holding means and concomitantly stirring predetermined liquid portions in said liquid-holding means by operation of said vibratory means.

9. In liquid supply apparatus:

(a) relatively movable liquid-holding means and liquid take-off means for the flow of predetermined portions of liquid from the liquid-holding means through said take-off means, in predetermined relative positions of said liquid-holding means and said liquid take-off means;

(12) electro-magnetically operated vibratory means for stirring predetermined liquid in said liquid-holding means;

(0) said vibratory means comprising a magneticallyresponsive carrier and a stirrer member fixed to said carrier for vibration therewith;

(d) solenoid means having a plunger electromagnetically coupled to said carrier for vibrating said carrier and thereby vibrating said stirrer member;

(a) spring means acting on said plunger to resiliently oppose the movement of said plunger into the coil of the solenoid and for biasing the plunger for movement in the opposite direction for corresponding movement of said carrier thereby; and

(f) spring means acting on said carrier for opposing said bias when the solenoid coil is deenergized.

References Cited in the file of this patent UNITED STATES PATENTS 2,543,818 Wilcox Mar. 6, 1951 2,590,007 Griswold Mar. 18, 1952 2,879,141 Skeggs Mar. 24, 1959 3,038,340 Isreeli June 12,1962 

1. IN LIQUID SUPPLY APPARATUS: (A) RELATIVELY MOVABLE LIQUID-HOLDING MEANS AND LIQUID TAKE-OFF MEANS FOR THE FLOW OF PREDETERMINED PORTIONS OF LIQUID FROM THE LIQUID-HOLDING MEANS THROUGH SAID TAKE-OFF MEANS, IN PREDETERMINED RELATIVE POSITIONS OF SAID LIQUID-HOLDING MEANS AND SAID LIQUID TAKE-OFF MEANS; (B) ELECTRO-MAGNETICALLY OPERATED VIBRATORY MEANS FOR STIRRING PREDETERMINED LIQUID IN SAID LIQUID-HOLDING MEANS; (C) SAID VIBRATORY MEANS COMPRISING A MAGNETICALLYRESPONSIVE CARRIER AND A STIRRER MEMBER FIXED TO SAID CARRIER FOR VIBRATION THEREWITH; (D) ELECTRO-MAGNETIC MEANS FOR ACTUATING SAID MAGNETICALLY-RESPONSIVE CARRIER, AND MEANS FOR ELECTRO-MAGNECTICALLY COUPLING SAID ELECTRO-MAGNETIC MEANS TO SAID CARRIER. 